Can't exit with return code 0

This line don't work with any branch of monsterwm.

```
 {  ALT|CONTROL|SHIFT, XK_q,          quit,              {.i = 0}}, /* quit with exit value 0 */
```

Also, I noticed that this shortcut : "Control+Alt+Shift+q" isn't working too, but even with another shortcut, monsterwm don't quit.
